Fritjof Helmchen

Title

Imaging 3D Neural Network Activity: A Glance at the Mesoscopic Scale in Neuroscience

Abstract

Nonlinear optical microscopy tools such as two-photon laser-scanning microscopy offer entirely new and fascinating views on brain dynamics. Using fluorescent indicators one can now record activity patterns in local neural circuits with single-cell resolution in the intact brain. These developments have the prospect of revealing principles of neural coding and plasticity at the intermediate scale of the brain. Here, I will give an overview of the state-of-the-art of imaging neural network activity in vivo. I will present novel labeling methods and innovative 3D laser scanning techniques for two-photon microscopy illustrated with examples from the neocortex and the cerebellum. In particular, I will describe a simple 3D laser scanning method that permits fast fluorescence measurements from several hundred cells distributed in 3D space. These advances may help to reveal fundamental operation principles of biological neural networks.